Various type of apparatuses are known for precisely positioning and for orientating a surgical instrument with relation to a patient's skull. The instrument may be inserted into the brain down to a precise location for taking a biopsy or for recording an epileptic site by an electrode or for other similar surgical procedures.
In an article published in the Journal of Applied Neuro-Physiology, Volume 46, pages 272 to 275, (1983) and entitled "A new headclamp for stereotactic and intracranial procedures", Andre Olivier, M.D. one of the present co-inventors and Gilles Bertrand, M.D. describe a semi-circular headclamp to be fixed to the patient's head for stereotactic and intracranial procedures. This headclamp, which is a part of the apparatus in accordance with the present invention, was then used in combination with the previously known Leksell stereotactic frame.
An advertising leaflet published in 1965 and entitled "Accessories for neurosurgery", describes a headclamp made of two pivoted parts with three spring loaded pins to engage the patient's skull and secure the headclamp in position on the skull. This headclamp, made by American Sterilizer is designed for use with three basic neuro attachments more particularly illustrated in the document.
U.S. Pat. No. 4,465,069 dated Aug. 14, 1984, entitled "Cranial insertion of surgical needle utilizing computer-assisted tomography", inventors: Jean-Yves Barbier and Christopher J. Moran describes a ring secured to the patient's head by rubber cushions and secured to the operating table by a ring mount. An instrument guide is adjustably supported by the ring.
U.S. Pat. No. 4,805,615 dated Feb. 21, 1989, entitled "Method and apparatus for performing stereotactic surgery", inventor: Mark P. Carol, describes and illustrates a positioning fixture which is designed to be secured to the patient's skull by means of self-tapping screws. The positioning fixture carries a ball collet which can be secured in any selected orientated position by a set screw. The ball collet has a through bore for slidable insertion of a surgical instrument, such as a pin.
U.S. Pat. No. 4,955,891 dated Sep. 11, 1990, entitled "Method and apparatus for performing stereotactic surgery", inventor: Mark P. Carol shows basically the same positioning device as in the previously noted U.S. Pat. No. 4,805,615.
U.S. Pat. No. 5,443,464 dated Aug. 22, 1995, entitled "External fixator apparatus", co-inventors: Thomas A. Russell and Harry E. Lee Jr., describes an apparatus for stabilizing bone fractures which includes a double chuck with ball collets and retaining nuts, to receive two retaining pins. Each ball collet has slits and both the axial position and the orientation of a pin is locked by a single retaining nut.
U.S. Pat. No. 5,618,288 dated Apr. 8, 1997, entitled "Stereotactic system for surgical procedures", inventor: Antonio M. Calvo, describes a frame which is secured to the patient's head by a plurality of fixing screws and which supports an arc-shaped member on which a slider is mounted to guide and hold a surgical instrument.
U.S. Pat. No. 5,649,936 dated Jul. 22, 1997, entitled "Stereotactic guide apparatus for use with neurosurgical headframe", inventor: Douglas D. Real, describes another type of apparatus for guiding a surgical instrument with precision within the patient's skull.
U.S. Pat. No. 5,695,501 dated Dec. 9, 1997, entitled "Apparatus for neurosurgical stereotactic procedures", co-inventors: Mark Carol, James L. Day, Erik G. Miller and Robert J. Riker, describes an apparatus for guiding a surgical instrument to a selected target within a patient's skull and along any selected path. The apparatus includes a positioning device similar to the one described in previous noted U.S. Pat. Nos. 4,805,615 and 4,955,891, and a headclamp to secure the patient's head with respect to the operating table or chair. An articulated arm is secured to the headframe and supports at its distal end a probe holder which has a ball and socket mecanism and an adjustment ball; probe holder may be manoeuvered about a patient's head and selectively locked into position for path evaluation, surgical instrument guidance or attachment of the hemispheric system. However, this arrangement does not provide a positioning device which may position with great precision a surgical instrument with its tip at a desired target within the patient's brain.